A great topic of debate is whether to outline your novel or not, and sound arguments can be made for both sides. I've written one novel without an outline, and one with. I've been working on and off for three years on the novel without an outline. The one with an outline was written in 17 days, revised and edited quickly, published and currently sitting on bookstore shelves. Hmmm . . .
Even given my own experience, I have to believe that some stories are just more suited to outlining than others. And outlining can be used for different purposes: (1) traditionally, the outline states in logical steps the progression of the plot; (2) an outline can help organize multiple story lines (see J.K. Rowling's outline for Order of the Phoenix below); (3) ordering events in an outline will often help an author see themes and patterns previously unrecognized.
So whether your outline looks like a flow chart, a spreadsheet, a Roman numeral list, or index cards taped to the wall, SOME form of organization will help you follow your own story. Just remember: an outline is not set in stone. It's always a work in progress.
Homework: As with all aspects of writing, give yourself permission to play with outlining. Look for a form that not only suits your brain style, but your story's style, too. For example, it might track a character's emotional journey instead of the events of a plot. An outline is simply a tool. Find a way to make it useful for YOU.
Author, writing coach, home school mom; native of the Pacific Northwest.